It is true that a great patience and steadfastness is needed. Be then firm and patient and fixed on the aims of the sadhana, but not over-eager to have them at once. A work has to be done in you and is being done; help it to be done by keeping an attitude of firm faith and confidence. Doubts rise in all, they are natural to the human physical mind—reject them. Impatience and overeagerness for the result at once are natural to the human vital; it is by firm confidence in the Mother that they will disappear. The love, the belief in her as the Divine to whom your life is given,— oppose with that every contrary feeling and then those contrary feelings will after a time no longer be able to come to you.
Ref: Letters on Yoga Vol. II